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I set my 632 motor up with Manley 221448 valve springs at 2.105, as I had clearance problems with a little bigger cam. After getting it put together I noticed the engine was very hard to turn. I started checking things and even though the springs were supposed to be set up at @.060 to coil bind which was 1.142, the bind measured at 1.168. So then I started looking for a 2.100 spring that had a coil bind bind number of 1.130 or less. I have 2 questions: Is this an anomaly, and does the only spring I could find (PSI 1248's) have the same problem with bind numbers being less than accurate? I don't any room to go to 2.150 as I am using lash caps and they won't work with the +.050 or +.100 retainers. It's an aluminum block with and the cam lift is .917 intake, .892 Exhaust, less valve lash. Valve lash is .016-.024. Any help appreciated.
 

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I set my 632 motor up with Manley 221448 valve springs at 2.105, as I had clearance problems with a little bigger cam. After getting it put together I noticed the engine was very hard to turn. I started checking things and even though the springs were supposed to be set up at @.060 to coil bind which was 1.142, the bind measured at 1.168. So then I started looking for a 2.100 spring that had a coil bind bind number of 1.130 or less. I have 2 questions: Is this an anomaly, and does the only spring I could find (PSI 1248's) have the same problem with bind numbers being less than accurate? I don't any room to go to 2.150 as I am using lash caps and they won't work with the +.050 or +.100 retainers. It's an aluminum block with and the cam lift is .917 intake, .892 Exhaust, less valve lash. Valve lash is .016-.024. Any help appreciated.
Are you attributing the hard to turn to the close proximity to coil bind? If so, that does not add up as according to your numbers you were still .030"-.040" from bind on the intake which would be no different than .060" from bind when rotating by hand.

Even without the lash caps, I would not switch to + locks. You want all your clamping below the groove. Not sure what spring locator you have? If it's .060" thick(most are), look at PAC part number PAC-S133. It's an ID locator that is only .030" thick, that may solve all your concerns.

As far as the tolerance on advertised coil bind height. The .026" is not shocking, we see more variance than that on some PAC springs. You need to check all the springs, they may vary a lot within a set. You may have some that are close enough to advertised to work on the intake side. The 1.168" bind will be very close to working on your exhaust if it's also 2.105" installed height.

I have used a ton of PSI springs although not their 1248's, they are typically better than most other brands relative to coil bind accuracy.

You could call someone like Joe Hornick who sales a lot of PSI and has the ability to measure CB, he may be willing to verify a set before sending them to you.
 

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Something doesn't sound right. Even if you don not consider lash, you are still .046 from bind. For any spring to be that far over advertised bind is hard.

With that being said, Logan mentioned the PAC seta which will work. Also the PAC-1248 would be an option if you truly are going into bind. Max bind is 1.130 and the actual bind will be below that max spec. There is also the PAC-1379L which binds at 1.100"
 
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